Keyboard switch apparatus



1965 H. v. AGUILAR ETAL 3,221,113

KEYBOARD SWITCH APPARATUS Filed Feb. 17, 1964 if fllllllllll 4 I ikml f! 17 4 ya NVENTORS. Z Mam? M49044? Li BY max/4w sr/mm A6 QM ATTOPWEX United States Patent 3,221,113 KEYBOARD SWITCH APPARATUS Hector V. Aguilar, Monterey Park, and Richard S. Mark, Arcadia, Calif., assignors to Clary Corporation, San Gabriel, CaliL, a corporation of California Filed Feb. 17, 1964, Ser. No. 345,367 3 Claims. (Cl. 200-5) This invention relates to electrical switching devices and has particular reference to keyboard operated switching devices.

Difiiculty has been encountered heretofore in constructing keyboard operated switches for electronic computing equipment or the like, particularly due to the fact that the keys of a manually operable keyboard are generally spaced apart a standard distance of approximately inch. This requires that the key ope-rated switches be similarly spaced while permitting assembly and replacemerit of different switches or key components when the latter are found to be defective.

Accordingly, a principal object of the present invention .is to provide a keyboard operated switching device which may be easily and quickly assembled or disassembled.

Another object is to provide a keyboard operated switching device which has a minimum number of parts.

Another object is to provide a keyboard operated switching device which is small and compact in size.

The manner in which the above and other objects of the invention are accomplished will be readily understood on reference to the following specification when read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a plan view, with parts broken away, showing a keyboard operated switching device embodying the present invention.

FIG. 2 is a front view, partly in section, of the switching device of FIG. 1.

Referring to the drawing, the keyboard switching device shown therein is intended to control ten different circuits or groups of circuits by manually depressing respective keys 11, ranging in value from 0 to 9.

The 0 key comprises a key top 12 integral with a double key stem 1314, slidably mounted in aligned slots 34 formed in two plates 15 and 16, formed of plastic or similar electrically insulating material. The other keys 1 to 9 comprise key tops 21 integral with individual key stems 24 which are also slideably mounted in aligned slots 34.

The plates 15 and 16 are held in spaced relation with each other by tubular spacers 17. The plates are supported below a keyboard top plate 18 having openings 20 through which the key tops, i.e. 21, of the keys extend. For this purpose, threaded supporting studs 22 are formed integral with the top plate 18. Screws 23 pass through the plates 15, 16 and spacer 17 and are threaded into the studs to hold the plate assembly in place.

Associated with each of the keys is an electric switch generally indicated at 25. Such switches may be of any suitable construction but are preferably of the type commercially available under the trade name Licon, model No. 4, and each has four electrical terminals 26 depending from the bottom thereof. Each switch is mounted on the bottom plate by forcing the terminals 26 thereof through tightly fitting holes 27 formed in the bottom plate 16. Electrical connectors 28 are subsequently soldered or otherwise attached to the downwardly projecting ends of the terminals.

Each switch includes a plunger 30 which actuates the switch contacts and is suitably yieldably pressed upwardly into engagement with a lever or element 31 pivoted at 132 to the switch body. The lever 31 underlies an ear 32 extending from the respective key stem, at right angles to the length thereof.

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In order to permit assembly of the keys in the guide slots 34 in the plates 15 and 16, additional slots 35 are formed in the upper plate 15, which slots communicate with the key guiding slots 34, thus permitting the ears 32 to be passed through the plate 15 to positions directly therebelow so as to engage with the switch levers 31.

Means are provided for retaining all of the keys in positions where their ears 32 are maintained in engagement with the switch levers 31. For this purpose, a retainer plate 36 is fitted over the top plate 15 and is interposed between such plate and the studs 22. The plate 36 has four laterally extending spaced arms, i.e. 37, which, when the retainer plate is in place, lie directly adjacent the sides of various ones of the key stems 13, 14 and 24. Each arm 37 has several downwardly extending ears 38 which extend through aligned ones of the slots 35 to maintain the ears 32 of the key stems below the surface of the plate 15 and in engagement with the levers 31.

In order to dis-assemble the switching device for replacement of defective switches or for other purposes, the

. screws 23 are removed, permitting the retainer plate to also be removed so that the various keys may be withdrawn upwardly from the plates 15 and 16. Thus, access may be readily had to any one or more of the switches.

In view of the foregoing construction, the switches 25 are mounted between the two spaced plates 15 and 16 and may be oriented at different angles relative to the key stems. For example, as shown in FIG. 1, the switches associated with the 1 to 9 keys are located at substantially 45 to a plane passing from front to rear of the keyboard. Although the invention has been described in detail and certain specific terms and languages have been used, it is to be understood that the present disclosure is illustrative rather than restrictive and that changes and modifications may be made without departing from the spirit or scope of the invention as set forth in the claims appended hereto.

Having thus described the invention, what is desired to be secured by United States Letters Patent is:

1. A key operated switching device comprising an upper plate having a key guiding slot therein,

a lower plate spaced from said first plate and having a key guiding slot therein aligned with said first mentioned slot, means supporting said plates in fixed relation to each other,

a key comprising a key top and a key stem attached at one end thereof to said key top;

said stem being insertable endwise at the opposite end thereof and downwardly in said aligned slots,

an electric switch mounted on one of said plates and extending between said plates, an actuator member for said switch,

a switch actuating ear extending laterally from said stem for actuating said member upon depression of said key,

said upper plate having a second slot therein communicating with said first mentioned guide slot,

said second slot permitting said ear to pass therethrough upon insertion of said stem into said key guiding slots,

and a retainer plate removably mounted on the top surface of said upper plate,

said retainer plate having an ear extending through said second slot to limit upward movement of said key stem.

2. A key operated switching device comprising an upper plate having a key guiding slot therein,

a lower plate spaced from said first plate and having a key guiding slot therein aligned with said first mentioned slot, means supporting said plates in fixed relation to each other,

a key comprising a key top and a key stem attached at one end to said key top;

said stem being insertable endwise at the opposite end thereof and downwardly in said aligned slots,

an electric switch mounted on one of said plates and extending between said plates,

said switch having a yieldable actuating element,

a switch actuating ear extending laterally from said stem in engagement with said actuating element whereby to actuate said switch upon depression of said key, said yieldable element normally maintaining said key in raised position,

said upper plate having a second slot therein communicating with said first mentioned guide slot,

said second slot permitting said ear to pass therethrough upon insertion of said stem into said key guiding slots,

and a retainer plate removably mounted on the top surface of said upper plate,

said retainer plate having an ear extending through said second slot to limit upward movement of said key stem.

3. A key operated switching device comprising an upper plate having a key guiding slot therein,

said stern being insertable endwise at the opposite end thereof and downwardly, in said aligned slots,

a switch actuating ear extending laterally from said stern,

an electric switch mounted on said lower plate and extending between said plates,

said switch having an actuating element yieldably pressing upwardly against said actuating ear whereby to normally hold said key in raised position,

said upper plate having a second slot therein communicating with said first mentioned guide slot,

said second slot permitting said ear to pass therethrough upon insertion of said stem into said key guiding slots,

and a retainer plate removably mounted on the top surface of said first plate,

said retainer plate limiting upward movement of said key stern by said actuating element.

References Cited by the Examiner UNITED STATES PATENTS 2,720,613 10/1955 Lustig 200-5 X 3,142,742 7/1964 Kaleba et al 200l68 X 3,193,607 7/1965 Anderson 2005 X KATHLEEN H. CLAFFY, Primary Examiner. 

1. A KEY OPERATED SWITCHING DEVICE COMPRISING AN UPPER PLATE HAVING A KEY GUIDING SLOT THEREIN, A LOWER PLATE SPACED FROM SAID FIRST PLATE AND HAVING A KEY GUIDING SLOT THEREIN ALIGNED WITH SAID FIRST MENTIONED SLOT, MEANS SUPPORTING SAID PALTES IN FIXED RELATION TO EACH OTHER, A KEY COMPRISING A KEY TOP AND A KEY STEM ATTACHED AT ONE END THEREOF TO SAID KEY TOP; SAID STEM BEING INSERTABLE ENDWISE AT THE OPPOSITE END THEREOF AND DOWNWARDLY IN SAID ALIGNED SLOTS, AN ELECTRIC SWITH MOUNTED ON ONE OF SAID PLATES AND EXTENDING BETWEEN SAID PLATES, AN ACTUATOR MEMBER FOR SAID SWITCH, A SWITCH ACTUATING EAR EXTENDING LATERALLY FROM SAID STEM FOR ACTUATING SAID MEMBER UPON DEPRESSION OF SAID KEY, SAID UPPER PLATE HAVING A SECOND SLOT THEREIN COMMUNICATING WITH SAID FIRST MENTIONED GUIDE SLOT, SAID SECOND SLOT PERMITTING SAID EAR TO PASS THERETHROUGH UPON INSERTION OF SAID STEM INTO SAID KEY GUIDING SLOTS, AND A RETAINER PLATE REMOVABLY MOUNTED ON THE TOP SURFACE OF SAID UPPER PLATE, SAID RETAINER PLATE HAVING AN EAR EXTENDING THROUGH SAID SECOND SLOT TO LIMIT UPWARD MOVEMENT OF SAID KEY STEM. 